Example of schedule
You can create a schedule to indicate that a type of employee works Mondays from 9am to 7pm and Tuesdays and Wednesdays from 8am to 6pm.
Your schedule is defined from three Time slots: one on Mondays from 9am to 7pm and two others for Tuesdays and Wednesdays from 8am to 6pm.
 
Example of time slot
A time slot is defined by the day of the week and the time that mark the beginning of the time slot as well as the day of the week and the time that mark its end.